Corrosion Resistance and Protective Coatings in Melted Al-Si Alloy of Heat Exchanger in Solar Thermal Power Plant

In the solar thermal power plant,the metallic materials are commonly used to improve the heat transfer rate and plasticity of the heat exchanger.Howevere,the melted Al-Si alloy may severely corrode metallic materials.20G high-pressure boiler steel was used for making specimens of the exchanger material under the circular conditions between 495 ℃ and 620 ℃ for a long time.TiB2,SiO2 and Al2O3 were used as the main composition of three kinds of high temperature coatings.The results indicated that the coatings could inhibit the diffusion of the microelements of energy storage material in the exchanger material,and resist corrosion effectively.